[Python-Dev] Making None a keyword

2002年4月25日 23:53:44 -0400

> I think it's a small project. We've got a new node type in the
> grammar -- None -- and we'll need a new opcode -- LOAD_NONE. The
> compiler just needs to generate a LOAD_NONE for every None node.
>> Does the parser prevent assignment to None? Or does the compiler need
> to check for the use of None in an assignment?

The compiler needs to check. It's just like assigning to a literal:
the parser has no power to prevent this, so the compiler has to act as
a safeguard.
--Guido van Rossum (home page: http://www.python.org/~guido/)